TFT-LCD (Thin Film Transistor Liquid Crystal Display) is a flat panel display, and is applied in high performance display fields increasingly because of its characteristics such as small volume, low power consumption, no radiation and the relatively low production cost.
As shown in FIG. 1A, a TFT-LCD consists of an array substrate 10 and a color film substrate 10′. A liquid crystal layer 12 is arranged between the array substrate 10 and the color film substrate 10′. In addition, the upper surface of the color film substrate 10′ is provided with a polarizer 13. The intensity of the light can be controlled by controlling the orientation of the liquid crystal molecules in the liquid crystal layer 12, with the filter function of the color film substrate 10′, color image display can be realized.
In order to eliminate the influence of the external light source on the display effect, in the existing manufacturing process of TFT-LCD, generally an AR (Anti-Reflective) film 14 is attached on a surface of the polarizer 13. The refractive index of the material of the AR film 14 is different with that of the material of the polarizer 13. In such a manner, for light incident to the AR film from a same point, a coherent addition will be performed for two reflected light beams, one of these reflected light beams being reflected at the interface between air and the AR film 14, the other being reflected at the interface between the AR film 14 and the surface of the polarizer 13, resulting in a destructive interference, thereby reducing the reflection.
However, the thickness of the AR film is related to the wavelength of the light that can be eliminated by the AR film. For example, when the thickness of the AR film is close to a quarter of the red light wavelength in the AR film, the AR film can then eliminate the reflected light of the incident light with a wavelength near red light wavelength. Therefore, the AR film can only achieve a zero reflection within a narrow wavelength range, and can not eliminate all the reflected light with wavelength of the visible light. Hence it reduces the effect of anti reflection. If, in addition, in order to improve the anti reflection effect, a plurality of AR films with different thicknesses are arranged on the polarizer 13, although they can effectively reduce the influence of visible light reflection on the display effect, meanwhile they will increase the thickness of the display, which is adverse to the ultrathin design of the display.